Update to latest testify version
Description
Currently, we are running an old version of testify we should update this. The newer versions have new methods that can be useful for us for testing.
Proposal
Instead of using a commit hash we should instead use a tag version to make it easier to find out what version and what is needed to upgrade. Also using tags will make dep status
throw a warning when it is outdated.
Links to related issues and merge requests / references
At this point, it is blocking !1058 (merged) since there some tests that depend on Maybe
func being available.